Publications by authors named "Nilson Branco"

In Brazil, Leishmania amazonensis is the etiological agent of cutaneous and diffuse cutaneous leishmaniasis. The state of Maranhão in the Northeast of Brazil is prevalent for these clinical forms of the disease and also has high rates of HIV infection. Here, we characterized the drug susceptibility of a L.

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Paromomycin is an aminoglycoside antibiotic approved in 2006 for the treatment of visceral leishmaniasis caused by Leishmania donovani in Southeast Asia. Although this drug is not approved for the treatment of visceral and cutaneous leishmaniasis in Brazil, it is urgent and necessary to evaluate the potential of this drug as alternative for the treatment against species responsible for these clinical forms of the disease. In Brazil, Leishmania amazonensis is responsible for cutaneous and diffuse cutaneous leishmaniasis.

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The protozoan Giardia duodenalis is one of the parasites of primary concern in drinking water treatment plants, due to its resistance to chlorination. Another matter of concern regarding chlorination of drinking water is the formation of disinfection by-products in the presence of precursors such as natural organic matter (NOM). In this study, the effects of ozonation (5 mg L) on G.

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Background: Enterocytozoon bieneusi are the most common microsporidia associated with different clinical manifestations such as diarrhoea, respiratory tract inflammation and acalculous cholecystitis, especially in immunocompromised patients. Infection usually occurs by ingestion of food and water contaminated with spores, but can also result from direct contact with spores through broken skin, eye lesions, and sexual transmission, depending on the microsporidian species. Although there are reports of E.

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Cerebral toxoplasmosis can be highly debilitating and occasionally fatal in persons with immune system deficiencies. In this study, we evaluated the Toxoplasma gondii-specific IgG subclass antibody response in 19 cerebrospinal fluid (CSF) samples from patients with cerebral toxoplasmosis who had a positive IgG anti-T. gondii ELISA standardized with a cyst antigen preparation.

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Background: Several species of protozoa cause acute or chronic gastroenteritis in humans, worldwide. The burden of disease is particularly high among children living in developing areas of the world, where transmission is favored by lower hygienic standards and scarce availability of safe water. However, asymptomatic infection and polyparasitism are also commonly observed in poor settings.

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Several series of tests have shown that fresh, intact samples of Giardia duodenalis and Cryptosporidium parvum (oo)cysts are not marked by fluorescent probes such as carboxyfluorcein-succinimidyl-diacetate-ester (CFDA-SE), C12-resazurin and SYTOX® Green, probably because of their robust cell walls. These dyes fail to indicate the viability of such protozoa and allow negative responses to be recorded from living and infectious samples. Cryptosporidium parvum showed stronger isolation from chemicals, with living oocysts remaining unstained by the probe for up to 90 days after extraction.

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The goals of this study were to investigate the occurrence of Cryptosporidium oocysts and Giardia cysts in main springs of Campos do Jordão, an important tourist city, in Brazil and to gather the largest amount of parasitological data from autochthonous population that live in rural areas of this city. The membrane filtration technique followed by direct immunofluorescence assay was employed for concentration and visualization of waterborne protozoa. In the period between June 2003 and May 2004, the presence of at least one pathogenic protozoa was detected in 25.

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The consumption of oysters and cockles, which are usually eaten raw or lightly-cooked, can cause outbreaks of human diseases, especially if these shellfish are harvested from polluted areas. In Brazil data about the occurrence of pathogens, like hepatitis A virus, in shellfish have been reported but research on natural contamination for pathogenic protozoa is still non-existent. Cryptosporidium oocyst contamination of oysters (Crassostrea rhizophorae) and cockles (Tivela mactroides) was evaluated during two different periods in a coastal area from São Paulo, Brazil.

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